From: Nicholas Piggin <[email protected]>
[ Upstream commit 8f51e3929470942e6a8744061254fdeef646cd36 ]
create_physical_mapping expects physical addresses, but creating and
splitting these mappings after boot is supplying virtual (effective)
addresses. This can be irritated by booting with mem= to limit memory
then probing an unused physical memory range:
echo <addr> > /sys/devices/system/memory/probe
This mostly works by accident, firstly because __va(__va(x)) == __va(x)
so the virtual address does not get corrupted. Secondly because pfn_pte
masks out the upper bits of the pfn beyond the physical address limit,
so a pfn constructed with a 0xc000000000000000 virtual linear address
will be masked back to the correct physical address in the pte.
Fixes: 6cc27341b21a8 ("powerpc/mm: add radix__create_section_mapping()")
Signed-off-by: Nicholas Piggin <[email protected]>
Reviewed-by: Aneesh Kumar K.V <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sasha Levin <[email protected]>
---
arch/powerpc/mm/book3s64/radix_pgtable.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c
b/arch/powerpc/mm/book3s64/radix_pgtable.c
index b4ca9e95e6781..c5cc16ab1954e 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -902,7 +902,7 @@ int __meminit radix__create_section_mapping(unsigned long
start, unsigned long e
return -1;
}
- return create_physical_mapping(start, end, nid);
+ return create_physical_mapping(__pa(start), __pa(end), nid);
}
int __meminit radix__remove_section_mapping(unsigned long start, unsigned long
end)
--
2.20.1
